<!DOCTYPE html>
<title>This iframe keeps a transaction on a database alive indefinitely to test</title>
<script>

// Keeps the passed transaction alive indefinitely (by making requests
// against the named store). Returns a function that asserts that the
// transaction has not already completed and then ends the request loop so that
// the transaction may autocommit and complete.
function keep_alive(tx, store_name) {
  let completed = false;
  tx.addEventListener('complete', () => { completed = true; });

  let keepSpinning = true;

  function spin() {
    if (!keepSpinning)
      return;
    tx.objectStore(store_name).get(0).onsuccess = spin;
  }
  spin();

  return () => {
    assert_false(completed, 'Transaction completed while kept alive');
    keepSpinning = false;
  };
}

async function run() {
  const dbs_to_delete = await indexedDB.databases();
  for (const db_info of dbs_to_delete) {
    let request = indexedDB.deleteDatabase(db_info.name);
    await new Promise((resolve, reject) => {
      request.onsuccess = resolve;
      request.onerror = reject;
    });
  }

  var openRequest = indexedDB.open('db-isolation-test');
  openRequest.onupgradeneeded = () => {
    openRequest.result.createObjectStore('s');
  };
  openRequest.onsuccess = () => {
    var tx = openRequest.result.transaction('s', 'readonly', {durability: 'relaxed'});
    keep_alive(tx, 's');
    window.parent.postMessage("keep_alive_started", "*");
  };
}

run();
</script>
